What's new
What's new

The art of hand scraping

bnem

Plastic
Joined
Nov 14, 2014
I'm in the process of trying to flatten the sole of a hand plane (#4). I originally tried Paul Sellers method of flattening the sole with sandpaper, but that only seemed to make things worse. I can only assume the sole was slightly convex to begin with and while sanding it the plane rocked back and fourth. I'm now left with a convex sole from front to back that's also slightly concave across the width of it. Anyway, I've moved on to trying to scrape it after having spent how many hours sanding. I've now spent how many hours trying to (learn to) scrape and fix the sole of this plane but with little success. I'm feeling defeated and am looking to you guys for help.

And before you start saying I need to search threads, I have. I've found many and read lots, but I still can't figure out what I'm doing wrong. Not to mention a lot of the images are dead so I'm left guessing what's going on.

The first way I tried to scrape was with a carbide scraper that's meant for paint. The blade angle is all wrong (the blade itself is at about 60 degrees on the handle) but the good thing is the blade is carbide. I was able to scrape a bit by playing with the actual cutting angle but it was very difficult to control.

The second way I tried was by taking an old US made Nicholson file and shaping the tip. This worked okay but I was only able to make a couple strokes before the edge was no longer keen.

Lastly, I figured I should buy the proper tool. I asked just about every store locally and no one knew what I was talking about. That's when I went to ebay. I was able to find some nice carbide scrapers but of course they wouldn't ship to Canada. Eventually I found a Rennsteig tool steel scraper. I figured it's German steel and it's designed for this so it should work. Needless to say I spent hours just trying to get the tip properly profiled and sharp because it was so poorly machined. When I finally did get it sharp it was no better than the hand file. I got a few scrapes and then the edge was toast. You could tell visually that the edge was gone.

Whatever method I tried I only ever got some gray fuzz. It was never a shiny curly piece of metal. I assume that depends on the type of material so I'm not sure whether or not this is correct for cast iron.

Anyway...can someone please tell me what I'm doing wrong? On the Rennsteig scraper I've made the one flat smooth and flat. The actual cutting edge is slightly convex with a 94 degree or so cutting angle. I find I often hold the scraper at about a 30 degree angle or so. I've tried lower but it doesn't seem to bite the metal and scrape. Either way, the cutting edge is gone in a few strokes.

I don't really have the tools to make my own carbide scraper or I would. I've wasted too many hours on this to give up now but I feel I'm getting pretty close.
 
Get a HSS parting blade and whip up a holder for it and use it horizontally. Make sure the edge is dead keen, and put some force into it.

lots of youtube videos on the subject, that's how I sorta learned and I do okay.

Richard King, RC99, Forrest Addy, Nick Muller, etc are the people to talk to. Respect their advice.
 
you are scraping cast iron so will only ever get 'grey fuzz'. oh and scraping is not an art, its a workshop technique no more difficult that tapping a hole - once you are shown the way. I'm not talented enough for artwork but have plenty enough abilities to scrape

as its specialized knowledge you will not find the tools or such in any store....but they are out there. Also, as it is a bit specialized, it takes a bit of effort to make/acquire the equipment. the Rennsteig scraper looks right, but afaik scrapers are sold without an edge put on. It it will need a very, very fine edge. The chip will be a tenth or two so if the edge is not super fine it will bounce over the work.

Files also make excellent scrapers how you need to do so heat treating. Files are case hardened (not carburized if you're wondering but heat treated so the inside is soft) so they don't break if you drop them. The result is the centre, where you ended up with an edge after grinding off the teeth is not hard. Proper way is grind off the teeth, forge into a fantail shape, anneal then heat treatd - water quench followed by straw temper.

I wrote a lengthy series of articles on scraping, probably more than you want for a plane sole, but it does cover all the basics. Back issue available from Home Shop Machinist.

gratuitous scraped plane shot

 
can someone please tell me what I'm doing wrong?

You just have yet to get a scraper - for scraping cast iron surfaces.

If you insist on buying something, get a SANDVIK (and not a cabinet scraper) or ANDERSON BROTHERS machine tool way scraper

Here is a recent beat looking Anderson Bros that was on Ebay

Anderson Bros Mfg Co Hand Held Scraper Solid Carbide Tool Machinist Scraping | eBay

Once you have one learn to sharpen it

Whether HSS or carbide, the edge is NOT sharp until it has been lapped to a mirror finish

Here is a Sandvik with already sharp insert type blades

Sandvik Coromant 620 20 Clamp on Scraper Plus 5 Free 620 2530 Carbide Insert | eBay
 
Some of the students in Sweden had a Rennsteig scraper I see they have a HSS scraperhttp://www.rennsteig.us/products/hardware/other-hardware-tools/975-flat-machinist-scraper.html

and a Carbide tipped one.

Rennsteig Tools, Inc. - Carbide Flat Scraper with replaceable four-blade carbide reversing plate and they look like a Sanvik handle but has 2 clamp screws. We found them to be to stiff as the Sanvik is. I have scraped many machines with a Sanvik but i cut and welded a 3" piece of bar stock to make it longer and more flexible. I see on the web-site above they sell Carbide tips. The bad deal about a carbide blade is you need a diamond wheel to sharpen it. On a recent thread we discussed buying engraving wheels off Ebay for 3 grits fr $55.00 I think. 260, 600 and 1200.

If you look at the link below, you will see on the first picture Lazlo had a Anderson with the wood handle, Sanvik with the Red Handle and a Biax with the blue handle.
http://www.practicalmachinist.com/v...achine-rebuilding-class-picture-heavy-230333/

You should buy the book Machine Tool Reconditioning or possibly one of the other guys can send you a link to an online copy, but Connelly has a chapter on hand scraping and sharpening a HSS blade on a wet stone. Also Lazlo has several pictures of scraping. One of the students from the GA scraping class we had 5 yrs ago scraped his planes and I am sure he took lots of photo's when he got back home. PM me with your email address and I'll send it to him so he can show you how. Where in Canada are you? Close to Vancuver? As Shane Carr is up there and could show you how. I hate to put in a plug, but you can buy a DVD on Ebay on scraping listed under BIAX plus there are several folks on here and else where who can teach scraping. Rich
 
Plenty of videos on youtube. Pics, or it never happened. Oh, and fly cut it.

Did manufacturers actually hand scrape wood planes?
 
I've looked on eBay and found those mentioned above but no one would ship to Canada. When one person finally said they would I caved and bought it (the Rennsteig) even though I was skeptical it would work. I'm not willing to dish out another $60+. With the time and money I've wasted I'm just looking to make what I've got work or find a quick and cheap way to whip one together. Right now I'm thinking of getting some steel rod, cutting a slit and then screwing the carbide tip in.
 
I have a question for the OP.... did you have the blade in the plane, ( albeit, retracted above the sole) and did you have it tensioned as it would be in real use while you initially "sanded" the sole ? ... also, what was the substrate that the initial work was performed upon ?

Brian :)
 
Blade was tensioned for use and retracted. I used 60 grit on a "flat" granite tile. The tile is flat for the accuracy I'm looking for. The plane is not. The plane was not flat to begin with.
 
I've made the most progress with the paint scraper I think. If I can make a better holder for the blade and make the profile rounder I'll be in good shape. I'll shorten my stroke too. But first I need to be able to actually scrape.
 

Attachments

  • uploadfromtaptalk1416100088084.jpg
    uploadfromtaptalk1416100088084.jpg
    96.4 KB · Views: 4,580
  • uploadfromtaptalk1416100111335.jpg
    uploadfromtaptalk1416100111335.jpg
    96.5 KB · Views: 1,470
  • uploadfromtaptalk1416100133204.jpg
    uploadfromtaptalk1416100133204.jpg
    97.8 KB · Views: 1,304
It does sound like you are having trouble getting an excellent edge on you blade. One easy way to check your edge is to test it on your thumbnail. If the edge is good the scraper should bite into the nail and not skate at a very shallow angle---like 5 degrees or less. If you are not seeing this degree of sharpness you will be frustrated.
To add to some of the good ideas already suggested:

There are many ways to get there. Fancy purpose-made sharpeners are very convenient but seem pricey to many. Simple diamond bench stones and hand laps can be used to acheive excellent results but may require more time. You likely already came across this thread.

http://www.practicalmachinist.com/v...you-using-sharpen-your-scraping-tools-286839/

I use the system shown in post 17. However, if it were a one-tme sharpening for very limited use, a careful worker could get a good edge just using a carbide bench stone and then finishing the edge with a bit of aluminum charged with green diamond paste. The motion on the convex tip would be a swiping motion parallel to the arc of of the tip and sliding over the stone and later the lap. The flat surface of the scraper--the bottom surface---could be just rubbed on the diamond stone and then finished on the lap. Using the aluminum lap charged with diamond paste I have been able to get a very fine edge. So you do not need fancy equipment to do the job. At its most basic you could use a diamond stone, a flat aluminum lap, and some patience. A powered lap as shown is a (unnecessary) convenience and purpose-built sharpeners a greater convenience.

It will also likely be a real help to use to a fairly powerful magnifier to inspect your edge. I like to use a 45X pocket microscope costing 6 bucks like this Amazon.com: Generic 45X Microscope Endoscope Pocket Magnifier Magnifying Loupe 2 LED Illumination: Home Improvement

Actually seeing the two planes of your cutting edge and how they converge (or not) takes a lot of the mystery out of the process.

Finally, like McGyver, I have scraped 3 of my cast iron planes improving their performance greatly. One little surprise for me was that I also found a sharp scraper I had been using on cast iron also allowed excellent localized and controlled scaping of shop-made wooden body planes to also true their soles.

Denis

 

Attachments

  • image.jpg
    image.jpg
    94.6 KB · Views: 4,271
I used 60 grit on a "flat" granite tile. The tile is flat for the accuracy I'm looking for.

Hmm.....

Granite tiles and sink counter tops are NOT flat! Pick up an import surface plate for scraping. The polish on the granite tile will not hold in transfer blue.

Lets say the tile was flat to within 5 thou, you can blue and scrape a few passes until the sole of the plane comes in to flatness. Now if you put the sole on a different place on the tile while bluing you'll get a wonky bluing pattern. It will drive you absolutely nuts and the plane will soon be on the floor, I guarantee it!
 
You should be able to get the thing serviceable flat on wet/dry paper stuck to any flatish surface with water.

If you still have a visible rocker on the sole- work on technique:

Work one direction till sole is marked with sanding scratches ( it matter little if still has rocker)
Change angle of attack to a few degrees and work a flat into sole- you will see the cross hatching on flat.
Keep going till the cross hatching covers entire sole.

You need a feel for the work.
If you are rocking the damn thing all over the place, no, it won't get flat.
 
Couple of things. As John O. suggests, Sandvik or Anderson Bros have a scraper you can live with for a long time. To sharpen it properly you need a Glendo Accu Finish which is mucho bucks. I just built my own from an electric motor and a VFD running at 8Hz Sketchy wiring I know, its corrected now. The diamond wheels come from China.





Here is the surface you want, imo, individual scrapes, need to go deeper with each scrape. Its pretty aggressive.



More, with sandvik pictured. Need to scrape with your upper body pushing imo.

 
I've made the most progress with the paint scraper I think. If I can make a better holder for the blade and make the profile rounder I'll be in good shape. I'll shorten my stroke too. But first I need to be able to actually scrape.

What are you bluing the plane up on? When you rub it do you swivel it or test to see if it is high in the middle. It looks like it is high in the middle to me. An easy way to do it is to hold the right side with your right hand and push it away from you 1" and then pull it toward you 2" and look down on it and see where it pivots. When it is flat it pivots at 30% from both ends. when you see where it pivots mark that spot with a sharpie and the release your right hand and do the same thing with your right hand. If it spins in the middle like I suspect take a .0015" feeler gage and press straight down on one side of the plane and see if you can slide in the feeler gage on the opposite side. if it fits loose try a .002...etc. Then divide that number by 2 and that how high it is in the middle. If you have a height gage and dial indicator you could put the indicator one one side and press down on each end and see how much it's high in the middle.

As far as sharpening your scraper PM me your email address or write me [email protected] and I will send you a copy of a few pages out of the Connelly book Machine Tool Reconditioning, showing how to sharpen your HSS blade. Your right, no need to buy anything else. Maybe you already have a lap stone, if not here is what you can buy Sharpening Stones | MSCDirect.com. I can also send you a few pages out of my notes that describes hand scraping. Plus tomorrow you can call me. I would be happy to help you. Rich

PS: If you make a grinder like the one Matt did you can buy a piece of carbide. I have some 1 x 1 Sandik i will sell you that you can make a clamp for your scraper. Enco sells 3 pieces of 1/16 x 1/4" x 1" carbide for $25.00, that you can silver solder to your scraper, but it isn't as good a quality as the Sanvik blade. Rich
 
I have a few Stanley and a longer No.6. They both have ground or lapped bottoms, no hand scraping.

I'd grind it then finish it off with scraping just for looks.

they don't come scraped, but they don't come that flat either. I maintain if they're not flat, it makes developing the feel of squaring and straightening the work with a hand plane that much tougher to come by - your feedback loop is all loopy

you're taking a risk grinding them, while they are obviously ground from the factory, I've heard tales of the heat from grinding causing problems of warping etc. Maybe BS, but no chance of it with scraping

Scraping also seems to make them glide better.....but that may just be like new running shoes making you run faster :D
 
Just for the record, it was implied above that the Sandvik scrapers are sharp and ready to use. It's true they're sharp, but they're not ready to use. I have two Sandvik scrapers, and both came with square blades and an inappropriate angle on the carbide edge. Both need to be addressed before they're ready to be used in anger. No idea what Anderson do, I don't have any of their scrapers.
 
I have a few Stanley and a longer No.6. They both have ground or lapped bottoms, no hand scraping.

I'd grind it then finish it off with scraping just for looks.

LOL i have a number 6 too im using to build the harwood conservatory. IMHO its a common off the shelf tool, use it to make something, don't just bling it up. Most good planes are plenty flat enough to make some really nice items as is from the factory :-) Worrying about a few tenths of bow on somthing as flexable as a plane being pushed across a bit of wood takeing at least a multiple thou shaving has so many error variables a few tenths on the base of the plane is not going to cause you errors in your actual work. If you want to do anything, practice planeing flat once you buy a working plane to start with, not the buggered up mess you have now!
 








 
Back
Top